TJ Jackson says his late uncle Michael Jackson was the ''greatest father''.

The 38-year-old singer - who is the legal guardian of the pop icon's children Prince, 19, Paris, 18, and Blanket, 14 - has opened up about the lessons he has tried to teach his cousins in the wake of their father's passing, saying their ''core ethics and values'' came solely from the 'Thriller' hitmaker himself.

Speaking to Barbara Walters for an Investigation Discovery special called 'Barbara Walters Presents: Michael Jackson: The Man in the Mirror', TJ said: ''I don't think there's anything I had to teach them because my uncle taught them everything they need to know.

''All the important things - their core ethics and values are so strong, and there's moments where I just hear my uncle's voice come out of them because [of] their love for people and their innocence.''

And the T3 singer says the one thing he does make sure his cousins understand is how lucky they were to have him as a parent.

He added: ''I don't even spend time on my uncle with them as a performer. I just try to make sure that they know their father was one of the greatest, greatest fathers. And that's why it's tough for me because he never got to finish his job as a parent.''

The news comes after Prince - the eldest son of the 'Billie Jean' singer, who died in 2009 - recently revealed his late father taught him ''what it is to be a man''.

He said: ''He taught me what it is to be a man; he showed me what it is to be a father. For me, [I want] to pass that on to my kids, or to help someone else who has kids. My cousin TJ [Jackson]'s kids, I treat them as if they were my kids. I have fun with them, I love watching them. That being said, I do hype them up, and they do get wild around me, but I think that would probably be the way to continue the teachings.''

'Barbara Walters Presents: Michael Jackson: The Man in the Mirror' premieres on Tuesday (20.12.16).